GB644548A - Improvements in or relating to grinding machines - Google Patents

Abstract

644,548. Grinding cutting tools. COOKE, E. A., and KAPELLA, Ltd. Aug. 26, 1948, Nos. 22460 and 23731. [Class 60] A machine for grinding cutters, such as milling cutters for. engraving machines, and of the kind having a detachable cutter holder G rotatable and longitudinally movable in guides D <SP>12</SP> on a carrier B<SP>4</SP> pivotally connected to the pedestal A of the machine has the holder provided with a fence G<SP>2</SP>, Fig. 10, relatively to which the cutter can be initially set, the initial rotational position of the holder with respect to the carrier being determined by a locating device on the latter. This locating device comprises a pawl D<SP>7</SP>, Fig. 5, pivoted to a plate which is angularly adjustable on a second, graduated plate D<SP>2</SP> secured to the carrier, the tip of the pawl being adapted to engage a rib G<SP>3</SP>, Fig. 10, forming part of the holder G. The fence G<SP>2</SP> receives a gauge strip M which is used to locate the flat face L<SP>2</SP> of the cutter with respect to the fence. The latter and the rib G<SP>3</SP> are formed on a drum G' connected by an indexing mechanism with the holder G which also carries an adjustable stop G<SP>5</SP> to co-operate with an elbow K<SP>1</SP> limiting the axial movement of the holder. The carrier B<SP>4</SP> is secured to a saddle B by a pivot having an axis ZZ and 'is adapted to be swung through an angle determined by two adjustable stops. A locking screw is also provided which, together with a scale B<SP>5</SP>, enables the carrier to be set ate any desired angle. The saddle B is adjustable along an axis Y-Y by a mircrometer head B<SP>1</SP> and may be inclined about this axis by means of two screws. In order to permit alignment of the axis PP of the holder G with the axis ZZ, the guides D<SP>12</SP> are slidably mounted on a base D pivoted at E and provided with a pin F, Fig. 5, which is engaged by a spring-loaded plunger F<SP>4</SP> and an adjustable stop F'. In operation, the cutter L' is correctly positioned in the holder by means of the gauge M' and the holder is then placed in the guides D<SP>12</SP>, the elbow K<SP>1</SP> being placed ever it. The pawl D<SP>7</SP> is adjusted to produce the desired clearance angle and the cone angle on the cutters obtained by setting the carrier to the appropriate angle about the axis ZZ. The in may also be adjusted to grind dovetail, parallel ball-end and other types of cutter. To grind helically-fluted cutters, a tooth rest 42 'is used'. This is brought to operative position by swinging it about a pivot 4<SP>4 </SP>mounted on a jockey displaceable in the direction of the axis of the holder, the pawl D' being inoperative. Straight-fluted cutters are ground using only the pawl D<SP>7</SP>. The cutting-edge may be checked by an inspection microscope provided on the pedestal A and equipped with a guide and locating device. The first Provisional Specification states that the machine may be used for grinding lathe cutters.